JPH06159258A - Hydraulic vane pump in which axial pressure balance and flowing characteristic are improved - Google Patents

Abstract

PURPOSE: To balance forces in cavities that tend to separate pressure plates by hydrostatic pressure by forming a circumferentially continuous hydrostatic pressure pool between a pair of pressure plate and its adjacent support plate respectively. CONSTITUTION: A hydraulic vane pump i.e., a rotary hydraulic device 20 includes a pair of pressure plates 36, 38 mounted on a pair of support plates 30, 32 in a housing 22 to cooperate with a surrounding cam ring 52 to form a cavity 62. A rotor 40 is rotatably disposed in the cavity 62, and has vanes 44 that radially engage a surrounding surface 53 of the cam ring 52. A circumferentially continuous hydrostatic pressure pool 90 is formed between each pressure plate 36, 38 and its adjacent support plate 30, 32. The forces in the cavities 62 that tend to separate the pressure plates 36, 38 are balanced by hydrostatic pressure. Thus, reliability over a long period of service time is obtained.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to rotary hydraulic devices capable of functioning as pumps, motors, shunts, pressure transducers and the like, and more particularly to vane pumps with improved pressure balance and flow characteristics. Is.

[0002]

BACKGROUND OF THE INVENTION Rotary hydraulic devices of the type described above generally are individually slidably disposed within a housing, a rotor adapted to rotate within the housing, and corresponding peripheral slots extending radially of the rotor. And a plurality of vanes formed. The cam ring radially surrounds the rotor,
It has an inwardly facing surface forming a vane track and one or more fluid pressure cavities between the cam surface and the rotor. Suction and discharge passages in the housing allow hydraulic fluid to be delivered to and discharged from the fluid pressure cavity.

US Pat. No. 4,505,654 discloses a balanced dual lobe rotary vane pump, in which the rotor cavity is formed by a cam ring and side support plates, and cheek plates, valve plates, port plates. , Or relatively thin pressure plates, also called flexible plates, are arranged between the support plate and the rotor. Each support plate has a pocket, which is surrounded by a seal.
The seal engages the pressure plates to form a hydrostatic pressure pool or pad between each support plate and its adjacent pressure plate. The discharge passage from the pump chamber extends through the pressure pool so that the pressure pool is filled with fluid at substantially discharge pressure. The fluid pressure in the hydrostatic pressure pool forces the pressure plate inward toward the rotor, balancing the force of fluid pressure in the pump chamber as well as the pressure distribution of the leaking fluid flowing between the rotor and the pressure plate, or A little over it. A vane slot in the rotor having an end hole cooperates with each vane to form a vane lower chamber at the axially outer end of each vane and an inner vane chamber at the middle of each vane. To form. The passages and grooves in the pressure plate and the radial holes in the rotor portion deliver suction pressure fluid to the vane lower chamber and discharge pressure fluid to the in-vane chamber, Push the vanes radially outward against the cam ring. Radial holes in the rotor portion communicate pressure within the vane volume to the end hole vane slots to reduce the vane's radial thrust on the cam surface.

[0004]

Although rotary vane pumps and other hydraulic devices of the type described above have received considerable commercial acceptance and success, further improvements are desirable. For example, providing a hydrostatic pressure pool as disclosed in the above U.S. patent improves the fluid pressure balance as compared to the prior art, but the pool is disposed adjacent to the discharge portion of the pump chamber. And therefore does not provide pressure support in the area of the pressure plate adjacent the suction portion of the pump. This lack of axial support is
Allows the pressure plate to locally deflect outwards, increasing the displacement of the displacement volume. Another problem arises due to the varying number of vane / rotor segments of the rotating groups disposed within each pressure chamber. For example, for a 10 vane pump, the number of vane / rotor segments in each pump chamber is
As the rotor rotates, it alternates in the order 2-3-2-3. The hydrostatic pressure pool is designed to provide an average hydrostatic pressure at pressure per displacement cycle equal to the individual pressure of 2.5 vane / rotor segments. It has been found that the axial balance on the pressure plate is sensitive to operating conditions affecting suction pressure and behaves poorly. Another technical problem is the audible noise and erosive wear associated with outgassing of dissolved air when the pressurized fluid undergoes throttling during precompression of the fluid volume entering the displacement chamber. The metering groove in the port of the prior art pressure plate provides a single stage throttling which results in significant outgassing. In the case of multistage throttling, the precompressed flow contains considerably less outgassing, which results in quieter operation and reduced erosion wear.

Accordingly, a general object of the present invention is a rotary hydraulic device, particularly a vane pump, which has improved operational integrity, improved efficiency, reduced audible sound level, and improved behavioral consistency. , Reduced sensitivity to speed changes, and / or reduced sensitivity to actuation at sub-atmospheric pressures. Another, more specific object of the invention is to provide a rotary hydraulic device having the above-mentioned properties, which exhibits an improved balance of fluid pressure against the pressure plate at all stages of operation. . A further object of the present invention is to provide a rotary hydraulic device, in particular a vane pump, which satisfies one or more of the above mentioned problems while at the same time being economical to assemble and reliable over a long operating life. That is.

[0006]

SUMMARY OF THE INVENTION A rotary hydraulic device according to the present invention comprises a housing having a support plate mounted to prevent rotation within the housing, and at least one pressure plate having an outer surface facing the support plate. Including. A rotor is provided for rotation adjacent the inner valve surface of the pressure plate and has a plurality of vanes disposed in corresponding vane slots. A cam ring is provided inside the housing to radially surround the rotor and form a vane track, and a radially inward facing surface, and at least one fluid suction cavity and at least one fluid discharge cavity between the cam ring surface and the rotor. And have.
A fluid suction passage and a fluid discharge passage feed hydraulic fluid to and discharge hydraulic fluid from the respective cavities. In a balanced dual lobe vane pump, which is a preferred embodiment of the invention disclosed herein, support plates and pressure plates are disposed on opposite sides of the rotor to cooperate with the cam ring to form the rotor cavity. ing. Identical arcuate fluid inlet and outlet cavities are formed on both diametrically opposed sides of the rotor and cooperate with diametrically opposed inlet and diametrically opposed outlet passages in the support and pressure plates. Fluid to and from the pump cavity.

According to one aspect of the invention, a hydrostatic pressure pool is formed between the outer surface of each pressure plate and the surface of the adjacent support plate facing it. These pressure pools are identical to one another and extend all around the axis of rotation of the rotor. The pressure pool is formed by a uniform thickness pocket or recess in each support plate and a continuous peripheral seal that engages the outer surface of the opposing pressure plate. The radial dimension of the pressure pool is smallest adjacent the two cavity suction passages, where the distribution of fluid pressure is smallest in the pump cavity. Further, this size is the maximum at a portion adjacent to the discharge passage for discharge, and the distribution of the fluid pressure is maximum there. In this way an increased axial hydrostatic pressure support for the pressure plate is achieved over the entire circumference of the axis of the rotating group.
The hydrostatic pressure on the pressure plate slightly exceeds the individual hydraulic pressure between the rotating rotor / vane group and the valve surface of the pressure plate.

A single continuous pressure pool provides a more uniform hydrostatic pressure to the pressure plate, which balances the separate hydrostatic pressures axially of the pressure distribution against the inner valve surface of the pressure plate, and / Or beyond.
The efficiency of the volumetric pump is improved, and the contact of the rotating group on the valve surface is light and uniform. The inner area surface of the support plate is provided with an axial relief, allowing the pressure plate to distort outward from the rotary group. This outward distortion addresses mechanical distortions induced by housing distortions and / or thermal gradients within the pump chamber. The outward distortion of the plate reduces the magnitude of the internal pressure distribution, and the resulting total hydrostatic pressure is significantly less than a constant magnitude hydrostatic pressure pool. This difference in hydrostatic pressure causes the pressure plate to
Restore to maintain a small operating clearance between the rotating group and the valve surface. If the operating clearance is reduced excessively (close to contact) as a result of the pressure plate being distorted,
The magnitude of the internal pressure distribution creates a hydrostatic pressure that exceeds the constant hydrostatic pressure of the pressure pool, causing the pressure plate to distort away from the rotating group. The distortion position of the pressure plate is continuously adjusted with respect to the pressure distribution on the valve surface. The pump is therefore less sensitive to the reactive support of the pressure containment (pump housing) and the external forces created by the large thermal gradients.

The second aspect of the invention, which may be practiced separately or in combination with the other aspects of the invention disclosed herein, is the rotor / chamber in the chamber.
It addresses the problem of variations in fluid pressure distribution within the pump chamber as a function of the number of vane segments. This number changes in the order N, N + 1, N, N + 1. N is a function of pump design and total number of vane / rotor segments. For example, U.S. Pat. No. 450
For the 10 vane pump shown in No. 5654, the number of vane / rotor segments subject to exhalation pressure in each pump chamber varies in the order 2,3,2,3 as the rotating group rotates. In accordance with this aspect of the invention, a second or supplemental hydrostatic pressure pool formed in each of the first or primary pressure pools adjacent the fluid discharge passage provides improved dynamic pressure balance. To be A timing port on the pressure plate cooperates with the passage of the rotor to intermittently deliver pressurized fluid from the discharge port on the periphery of the rotor to a second or auxiliary hydrostatic pressure pool located on the support plate. To do.
Preferably, the passages in the rotor consist of a plurality of passages individually arranged between adjacent vanes.

In this way, the hydrostatic pressure exerted by the first and second pressure pools varies as a function of rotor rotation and thus the number of vane / rotor segments in the pump chamber. That is, the ports of the pressure plate and the passages of the rotor that are open to the secondary pressure pool have a positive fluid flow when three (N + 1) vane / rotor segments are operatively placed in each of the pump chambers. Is pumped from the pump chamber to the secondary pressure pool and only two (N) vane / rotor segments are placed in the pump chamber so that the pressurized fluid escapes to the suction of the secondary pressure pool. It is arranged. The segmented or continuous primary pressure pool according to the first aspect of the invention described above exerts a supporting pressure on the pressure plate when two (N) vane / rotor segments are arranged in the pump cavity. And the auxiliary pressure pool is designed to exert a supporting pressure on the pressure plate with an amount corresponding to the additional or third vane / rotor segment. At rated operating conditions, the hydrostatic pressure of the pressure pool balances or slightly exceeds the total hydrostatic pressure of the internal pressure distribution on the pressure plate. The resulting more uniform force distribution on the side plates reduces local contact wear by the vane / rotor rotating groups. This pump can better cope with conditions affecting suction pressure, such as high pump speeds, reducing the magnitude of the pressure distribution in the rotating group. Volume efficiency is also improved.

According to a third aspect of the invention, which may also be implemented separately from or in combination with other aspects of the invention, an isolation region within each hydrostatic pressure pool defines a passageway. Strategically positioned to use a multi-stage orifice to throttle the flow of exhaled fluid, providing a place for precompressing the vane volume to exhalation pressure levels prior to displacement in the exhalation quadrant. The precompressed flow is
It occurs in the spitting chamber. This pre-compressed flow is directed through the rotor radial holes and into the vane lower chamber. This chamber directs flow into pockets strategically positioned in the pressure plate when aligned. This flow enters this pocket, which contains an orifice of a certain size, and continues to a passageway located in an isolated area within the surrounding hydrostatic pressure pool. The flow of precompressed fluid continues through a second orifice in the passageway and passes through a third orifice positioned in a subsequent pocket. When aligned, this flow enters the subsequent vane lower chamber, through the rotor radial holes,
It continues into the vane volume at the transition residence between suction and exhalation. The vane volume is pressurized to the exhalation pressure level with minimal outgassing. In conventional configurations, metering grooves are used to squeeze the pressurized fluid into the vane internal volume for precompression. This single-stage orifice produced a significant amount of outgassing, which contributed to noise and erosive wear of the pump chamber. The multi-stage orifice of the present invention is essentially a series of thin blade orifices arranged in series. This configuration prevents or reduces cavitation (outgassing of dissolved gas in the fluid) by reducing the pressure gradually rather than suddenly.

[0012]

The invention, together with its additional problems, features and advantages, will be best understood by referring to the following description, claims and accompanying drawings.

1-3 illustrate a vane pump 20 according to one presently preferred embodiment of the present invention, which comprises a housing 22 having a body 24 and a cover 26. A vane pump subassembly or cartridge 28 is provided between the body 24 and the cover 26. Cartridge 28 includes a first support member or support plate 30 adjacent body 24 and a second support member or support plate 32 within cover 26. Support plate 3
0, 32 have surfaces facing each other at intervals in the axial direction of the drive shaft 34 of the pump. The pressure plate 36 has an outer surface facing adjacent the support surface of the support plate 30 and also includes a second pressure plate 3
8 has an outer surface facing the support surface of the support plate 32 adjacent thereto. The pressure plates 36, 38 are of substantially uniform thickness and have axially opposed inner valve surfaces. As mentioned above, the pressure plate 3
6,38 are also referred to in the art as cheek plates, port plates, and flexible plates. Pump timing is characterized on valve surfaces positioned on pressure plates, flexible plates, etc.

A rotor 40 is disposed between the inner surfaces of pressure plates 36, 38 and is rotatably connected to a spline on drive shaft 34. Rotor 40
Has a plurality of generally radially extending slots 42, each having a radially slidable vane 44 disposed therein. The inner end of each vane slot 42 terminates in a vane lower chamber 46. A circumferential groove 48 positioned on the inner valve surface of each of the pressure plates 36 and 38 communicates with the expelled volume in the pool 90 to direct pressurized fluid via the axial passage 151 in each vane slot 42. The vanes 44 are supplied to and fed to the in-vane chambers 50 arranged substantially in the middle of the radial length of each vane 44. A cam ring 52 radially surrounds the rotor 40 and has a radially inward facing cam surface 53. It cooperates with the rotor 40 to define a diametrically opposed arcuate pumping event between the cam ring and the rotor. Pump events consist of suction, preload, exhalation, and depressurization. This pump cycle occurs twice per revolution. The cartridge 28 has a plurality of screws 5
Form a sandwich-like assembly held by 6. The housing cover 26 and the body have screws 58.
Are fixed to each other by means of the cartridge 28 and the cartridge 28 is held therein.

The housing 22 opens into a suction cavity 62 in the cover 26 and supports plates 30, 32.
Open to the suction passage 64 at
6 and 38 has a fluid suction 60 that opens into a kidney-shaped suction port 68 in one of the expansion vane chambers through a suction passage 66. Support plate 3
The suction passage 66 at 0 also opens into a passage 70 in the support plate 30 and from there through an opening 72 in the plate 36, through a matching vane lower chamber 46, then in the plate 38, an opening 72, a support. A passage 74 in the plate 32 and a cavity 76 formed by the cover 26 open to a kidney-shaped suction port 68 in a radially opposite chamber in the expansion vane. Suction fluid is thus supplied to the in-vane chambers and to the common lower vane chamber 56.

The pressurized intra-vane chamber 50 provides a radial force to maintain the vanes 44 in contact with the cam surface at the suction during preload and vacuum pump cycles. The radial groove 78 connected to the suction passage 70 and the area around the shaft 34 are arranged to drain pump leakage and prevent pressurization of the shaft seal 150. Within the pump chamber, two axially opposed kidney shaped discharge ports 80 on the plates 36, 38 direct the discharge fluid into the pool 90 and through the passageway 84 as shown in FIG. It is arranged to discharge into an opening 88 in the body 24. The diametrically opposite position of port 80 balances radial forces on shaft 34 and against support bearings 153, 154, as shown in FIGS. As far as the description so far,
Pump 20, in both construction and operation, is substantially similar to those disclosed in the aforementioned US Pat. No. 4,505,654. Reference is made to this US patent for details of the description.

According to the first aspect of the present invention, a circumferentially continuous hydrostatic pressure pool 90 is provided for each plate 30, 3.
2 and the associated pressure plates 36, 38 adjacent thereto. The pools 90 are the same as each other, and extend around the entire circumference of the rotation axes of the rotor 40 and the shaft 34. Each pool 90 includes an inner resilient seal 92 (best shown in FIGS. 2 and 3) that surrounds the first or open inner end of the shaft 34 and passage 70, a seal 92 and a spout opening 84. And a second or outer elastic seal 94 defining the perimeter of the. The seals 92 and 94 are
It is compressed against the outer surfaces of the facing pressure plates 36, 38. The seals 92,94 thus cooperate with the support plates 30,32 and the pressure plates 36,38 to form a hydrostatic pressure pool 90 on either side of the pump cavity. The pool 90 has a smaller radial dimension between seals radially inward of the suction opening 64 and a larger radial dimension adjacent and adjacent the perimeter of the discharge opening 84. Plates 30, 3
The axial thickness of the pool 90 defined by the depth of the pockets formed in 2 is substantially constant, except for the axial relief 156 shown in FIGS. Since the fluid at discharge pressure flows into each hydrostatic pressure pool, and actually through the pool 90 between the support plate 30 and the pressure plate 36, the pressure plates 36, 38
A hydrostatic pressure clamping force is applied to the outer surface of the.

A circumferential groove 48 positioned on the inner valve surface of each of the pressure plates 36 and 38 has a pool 9
0, which is in communication with the discharge volume at 0 and supplies a pressurized flow via an axial passage 151 in each vane slot 42, and as shown in FIGS. 1 and 2, the radial length of each vane 44. Supply is performed to the chamber 50 in the vane arranged approximately in the middle of the height. In the pump chamber, plate 3
Two axially opposed kidney-shaped exhalation ports 80 formed in 6 and 38 direct the exhaled fluid into pool 90 and through a passage 84 an opening in housing body 24 as shown in FIG. It is positioned to exhale to 88. A second pair of ports 80 are positioned diametrically opposite to balance the radial forces on shaft 34 and support bearings 153, 154 as shown in FIGS.

4A and 4B and 5 illustrate the operation of circumferentially continuous hydrostatic pressure pool 90 in accordance with this aspect of the invention. The arrows shown in FIGS. 4A, 4B, 5 and 6 schematically indicate the direction and magnitude of the fluid pressure distribution with respect to the pressure plate. Adjacent to the discharge opening 84, the pool 90 has a maximum radial dimension and therefore a hydrostatic pressure 90 against the outer surface of the pressure plates 36, 38 to counter the pressure distribution within the pump chamber.
exert a. Also, the pressure distribution 54a in the pump chamber,
It is also in this area adjacent to the discharge opening 84 that 54c and 54d exert a hydrostatic pressure on the inner surface to try to separate the pressure plates. On the other hand, adjacent to the suction passage 70, the pressure pool 90 has a smaller radial dimension and therefore exerts a smaller hydrostatic pressure 90b on the outer surface of the pressure plate. It is also in this region that the fluid pressure distribution in the pump chamber is smaller. Thus, the circumferentially continuous hydrostatic pressure pool 90 of the present invention provides no pressure of the hydrostatic pressure pool on the pressure plate, and in particular on the outer surface of the pressure plate in the prior art as shown in FIGS. It provides a better pressure balance to the unsupported area adjacent to the suction port.

FIGS. 4A, 4B and 5 show a relatively uniform pressure distribution 54c between the rotating group and the valve surface of the pressure plate. Changes in the structural content of the pump cartridge and wide temperature gradients can distort the valve surfaces of pressure plates 38 and 36. The change in the axial gap between the rotating group and the valve surface is
It affects the pressure distribution 54c. The reduction of the axial clearance limits the leakage flow and increases the size of the pressure distribution 54d (FIG. 4).
(A)). The total hydrostatic pressure exceeds the total hydrostatic pressure of the pool 90 (90a plus 90b) and the pressure plate is biased outwards to avoid making contact with the rotating group.
If the pressure plate were to be biased outwards by the excess amount allowed by the axial relief 156, the pressure distribution would decrease to something like 54b in FIG. 4B, with a smaller hydrostatic pressure in the pool 90. It comes to counter the total hydrostatic pressure (90a plus 90b). This difference in pressure causes the pressure plate to return, resulting in a smaller axial clearance in the rotating group. This balancing process is
Continue until axial force balance is achieved. The result of this pump feature is improved volumetric efficiency, greater thermal shock capability, and reduced seizure events in the rotating group.

7-15, various modifications and variations in accordance with the present invention are shown, where the same reference numbers as previously used with respect to pump 20 shown in FIGS. 1-5 are the same or equivalent. , And reference numbers with suffixes indicate related, but modified components.

FIGS. 7-10 selectively communicate via a rotor to a pump chamber to more accurately support the axial hydrostatic separating and clamping forces imposed on the pressure plate. , Shows a pump 100 featuring a multi-zone hydrostatic pressure pool. The separation force between the rotating group of vanes / rotors and the flexible pressure plate varies depending on the number of vanes / rotor segments that are subject to the discharge pressure in the pump chamber. For example, in a 10 vane rotation group, the number of vane / rotor segments that are subject to exhalation pressure per pump chamber varies in 2-3-3-3 order as the rotor rotates. In conventional vane pumps of the type disclosed in the aforementioned U.S. Pat. No. 4,505,654, and also in the pumps 20 previously disclosed with respect to FIGS. 1-5, the hydrostatic pressure pool area has an average of 2.5 discharge pressures. It is designed to support vane / rotor segments, thus a compromise between a maximum of 3 segments and a minimum of 2 vanes per pump cycle. However, according to the embodiment of the present invention illustrated in FIGS. 7-10, separate isolated regions within each hydrostatic pressure pool are sequentially communicated to the exhalation and inhalation via the rotor to reduce exhalation pressure. A hydrostatic pressure clamping force is applied to the pressure plate with respect to the separation forces that occur for the two and three vane / rotor segments it receives. The main hydrostatic pressure pool minus the two isolation regions is designed to equal or slightly exceed the hydrostatic separating force at the discharge pressure caused by the pressure distribution of the two vane / rotor segments per discharge cycle. Has been done. The auxiliary isolation pool area is designed to be pressurized when the three vane / rotor segments are at discharge pressure. Under the latter operating conditions, the hydrostatic pressure of the pool is equal to or slightly above the separating force.

Referring to FIGS. 7-10, the support plate 1
02 and a support plate on the opposite side in the axial direction (not shown)
Has an isolation region 104 in each of the pressure pools 90c surrounded by a seal 106 that engages the outer surface of the facing pressure plate 36a (or 38a). As best shown in FIG. 8, the recess formed by the surface of the support plate 102 defines an isolation region 104.
Is shallower than in the main pressure pool 90c. The pressure plate 36a has an axial passage 108 which opens into the region 104, which allows the rotor 40a to rotate as the rotor rotates.
Located in axial alignment with the lower vane chamber 46 at. The lower vane chamber 46 is also in communication with the periphery of the rotor via the radially angled rotor passages 110, and thus in the vane interior pressure. The passages 108 in the plate 36a are aligned with the vane lower chamber 46 as shown in FIG. 10 when the three vane / rotor segments in the adjacent pump chambers 51 are at discharge pressure, and the two vane / rotor segments are When it is at the discharge pressure, it is positioned so as to let the pressurizing region 104 escape to the suction pressure, that is, the port 64 as shown in FIG. In this way, fluid at substantially discharge pressure is intermittently delivered to region 104 as a function of rotor rotation, due to the higher number of vane / rotor segments being at discharge pressure. Resulting in extra clamping pressure at a time corresponding to the presence of extra separation pressure. Auxiliary port 1
It will be noted that the fluid pressure at 04 increases as the chamber 46 moves into alignment with the passage 108, reaches a peak at the time of perfect alignment, and then decreases as the chamber moves out of alignment. The passages 108 are sized and positioned to synchronize with the number of vane / rotor segments that are at pressure for compression and relief of the isolation region within the hydrostatic pressure pool.

In FIGS. 11 and 12, the main hydrostatic pressure pool 90 is used to position the multi-stage orifice.
A secondary isolated hydrostatic pressure pool region 104 is used in c to pre-compress the fluid in the vane volume that is about to enter the discharge cycle, and to provide a higher dynamic to the pressure plate. Pump 120 for pressure balance
It is shown. These multi-stage orifices significantly reduce outgassing, reduce or eliminate air bubbles in the fluid, and also contribute to audible noise and erosion associated with air bubbles, as compared to prior art pump structures with single-stage metering grooves. The wear is thereby reduced. The passage 108a in the pressure plate 36b is positioned to align with the vane lower chamber 46 of the rotor 40a, as in the pump 100 (FIGS. 7-10). Channels or passage grooves 122 in region 104 interconnect the passages 108 in adjacent pressure plates. Channel 122 allows fluid flow between adjacent vane / rotor segments to
And 12 to orient as shown by the directional arrows to pre-compress the vane volume to discharge pressure prior to displacement during the discharge cycle. The series of orifices 108w, 124 and 108x are sized to stage the depressurization and precompress the vane volume. This pressure staging reduces the amount of outgassing associated with throttling the high pressure flow.

In the pump 130 shown in FIG. 14, the features of pre-compression and reduced outgassing in the embodiment of FIGS. 11-13 differ from the support plates with separate pressure plates previously described. It is obtained in a pump with a distinct, rigid support plate 132. Following casting and machining of the support plate 132,
Holes 134 are drilled at an angle through this plate to open the passage 10 open to the lower vane chamber of the rotor.
8a, 108w, 108a and 108x are connected to each other. Next to the outer end of the hole 134,
136 and the passageway 108 and passageway 122 are separated from each other by separate pressure plate 36b and support plate 10.
2a, as in the embodiment of FIG. 12, formed in each of the passages 108a, 108w, 108a, 1
A passage 122a is left connecting the 08x to each other.

FIG. 15 shows the above-mentioned US Pat. No. 45056.
Formed by seal 146 as in No. 54,
Pump 142 with isolated hydrostatic pressure pool 144
The support plate 140 of No. 1 is shown, which is to be distinguished from the circumferentially continuous hydrostatic pressure pools 90, 90c. A separate isolation region 104 is formed by the seal 106 within each pool 144. As described above with respect to FIG.
4 is formed. Thus, FIG. 15 shows that both the isolated hydrostatic pressure pool 104 and the liquid precompression feature provided by the passageway 122 and the restriction 124 can be implemented in a pump having an isolated main pressure pool 144. It is shown.

[0027]

As described above, according to the present invention, first, the hydrostatic pressure pool is formed so as to extend in the entire axial direction. An increase in the axial hydrostatic pressure support for the pressure plate is thus achieved around the axis of the rotating group.
The volumetric efficiency of the pump is improved and the contact of the rotating group with the valve surface is light and uniform. An axial relief is provided on the surface of the inner area of the support plate, allowing the pressure plate to distort outwards from the rotating group, induced by housing distortion and / or thermal gradients in the pump chamber It becomes possible to deal with mechanical force.

Also in accordance with the present invention, an auxiliary hydrostatic pressure pool is formed in each of the main hydrostatic pressure pools, with pressurized fluid flowing from the discharge port at the periphery of the rotor to the auxiliary hydrostatic pressure pool as a function of rotor rotation. And intermittent feeding results in a more uniform distribution of forces on the side plates and can reduce local contact wear by the vane / rotor rotating groups. Thus, conditions that affect the suction pressure, such as high pump speeds, can be better addressed, reducing the size of the pressure distribution in the rotating group and improving volumetric efficiency.

Further in accordance with the present invention, a multi-stage orifice that throttles the flow of exhaled fluid can be used to pre-compress the vane volume to exhalation pressure levels prior to displacement in the exhalation quadrant. By gradually reducing the pressure, cavitation (gas release of dissolved gas in the fluid) is prevented and erosion wear is also reduced.

[Brief description of drawings]

FIG. 1 shows a side elevation of a balanced dual lobe rotary vane pump according to a presently preferred embodiment of the invention,
FIG. 3 is a cross-sectional view taken substantially along line 1-1 of FIG. 2.

2 is a partial cross-sectional view taken substantially along the line 2-2 of FIG.

FIG. 3 is a view taken substantially along line 3-3 of FIG.
3 is an elevational view of a support plate of the pump of FIG.

4 (A) and (B) are schematic diagrams showing fluid forces on a pressure plate under different operating conditions in the pump of FIGS. 1-3.

FIG. 5 is a schematic diagram showing fluid forces on a pressure plate under different operating conditions in the pump of FIGS. 1-3.

FIG. 6 is a schematic diagram similar to FIGS. 4 and 5, showing fluid forces on a pressure plate according to the prior art.

FIG. 7 is an elevational view of a support plate similar to FIG. 3, showing a modified embodiment of the present invention.

8 is a partial cross-sectional view taken substantially along the line 8-8 of FIG.

9 is a partial cross-sectional view similar to FIG. 2, showing the modified embodiment of FIG. 8 in two stages of operation, with FIG. 10;

10 is a partial cross-sectional view similar to FIG. 2, showing the modified embodiment of FIG. 8 in two stages of operation, in conjunction with FIG. 9;

FIG. 11 is a partial cross-sectional view showing another modified embodiment of the present invention.

12 is a partial cross-sectional view taken substantially along the line 12-12 of FIG.

FIG. 13 is an elevation view of a support plate similar to FIG. 3, showing a further modified embodiment of the invention.

14 is an elevation view of a support plate similar to FIG. 3, showing a further modified embodiment of the present invention.

15 shows a further modified embodiment of the invention, FIG.
FIG. 6 is an elevational view of a support plate similar to FIG.

[Explanation of symbols]

 20 vane pump 22 housing 28 cartridge 30 and 32 support plate 34 drive shaft 36 and 38 pressure plate 40 rotor 42 slot 44 vane 46 lower vane chamber 48 circumferential groove 50 vane inner chamber 52 cam ring 62 suction cavity 64, 66 suction passage 68 suction port 80 Discharge port 84 Discharge opening 88 Opening 90 Hydrostatic pressure pool 92,94 Seal 100 Pump 104 Isolation area 108 Axial passage 153,154 Support bearing

Claims (43)

[Claims] 1. A rotary hydraulic device, the housing including a support means provided in the housing for rotation and having a support surface, the support means having an outer surface facing the support surface and an inner surface. An upper pressure plate, a rotor provided for rotation adjacent to the inner surface of the pressure plate, a plurality of slots and a plurality of vanes within the slots, and within the housing radially surrounding the rotor. A cam ring having a radially inwardly facing surface defining a vane track and at least one fluid pressure cavity between the surface and the rotor; and for delivering fluid to the pressure cavity. Suction of fluid, including suction passage means, and discharge passage means for delivering fluid from the pressure cavity. And a means for forming a hydrostatic pressure pool between the outer surface of the pressure plate and the supporting surface of the supporting means facing it, the pressure pool of the rotating shaft of the rotor. A rotary hydraulic device extending over the entire circumference, the pressure pool being coupled to the discharge passage means such that the fluid in the pressure pool operates at substantially discharge fluid pressure. 2. The device of claim 1, wherein the means for forming the hydrostatic pressure pool comprises a recess of substantially uniform thickness around the entire axis of rotation. 3. The device of claim 2 wherein said discharge passage means extends from said pressure cavity and through said pressure pool. 4. The pressure pool has a non-uniform radial dimension about the axis and a minimum radial dimension in the pressure cavity from a radially inner side of the suction passage means, The device of claim 1 having a largest radial dimension adjacent said discharge passage means. 5. The device of claim 4, wherein the pressure pool has at least a portion of axial thickness that is substantially uniform over the circumference of the shaft. 6. The means for forming the pressure pool comprises:
Including first means for forming a first pressure pool extending around the circumference of the shaft, the first means being such that the fluid in the first pressure pool is at a continuous, substantially exhaled pressure. And means for connecting the first pressure pool to the discharge passage means, and forming a second pressure pool and a timing passage means for intermittently connecting the second pressure pool to the pressure cavity. The device of claim 1 including second means, wherein the hydrostatic fluid pressure applied to the pressure plate by the first and second pools varies as a function of rotation of the rotor. 7. The device of claim 6, wherein the second pressure pool is radially surrounded by the first pressure pool. 8. The device of claim 7, wherein the timing passage means extends through the rotor and the pressure plate. 9. The timing passage means extends through the rotor and opens adjacent to the pressure plate, and the timing passage means is intermittent with the first timing passage means when the rotor rotates. 9. The device of claim 8 including second timing passage means on the pressure plate arranged to align with. 10. The device of claim 9 wherein said first timing passage means in said rotor comprises a plurality of first timing passage means each disposed between adjacent pairs of vanes. 11. A vane / timing passage means in the rotor and pressure plate wherein the fluid pressure in the second pool is in the fluid pressure cavity between the suction passage means and the discharge passage means.
11. The device of claim 10, arranged and arranged to vary as a function of the number of rotor segments. 12. The rotor and cam ring have a number of vane / rotor segments in the fluid pressure cavity of N, N + 1, N, N + 1. ． ． And N is configured to be a non-zero integer, and the timing passage means includes the second pressure from the pressure cavity when the N vane / rotor segment is in the pressure cavity. Blocks the flow of fluid to the pool, N
12. The device of claim 11, wherein fluid flow is released from the pressure cavity to the second pressure pool when there are +1 vane / rotor segments in the pressure cavity. 13. The timing passage means in the rotor and pressure plate are configured and arranged to communicate with two adjacent vane / rotor segment skeins in the pressure cavity simultaneously with the second pressure pool. The device according to claim 10. 14. The vane / rotor segment at a higher pressure, wherein the second means forming the second pressure pool comprises passage means interconnecting the timing passage means in the pressure plate. Fluid in one of the vanes / rotor segments at a lower pressure through the timing passage means and the passage means in the second pressure pool to the other of the vane / rotor segments to predict fluid in the other segment. The device of claim 13, wherein the device compresses. 15. The device of claim 14, wherein the passage means in the second pressure pool comprises an orifice. 16. A rotary hydraulic device, the housing comprising a support means provided in the housing for rotation and having a support surface, the support means having an outer surface facing the support surface and an inner surface. An upper pressure plate, a rotor provided for rotation adjacent to the inner surface of the pressure plate, a plurality of slots and a plurality of vanes within the slots, and within the housing radially surrounding the rotor. A cam ring having a radially inwardly facing surface defining a vane track and at least one fluid pressure cavity between the surface and the rotor; and for delivering fluid to the pressure cavity. Suction of fluid including suction passage means, and discharge passage for feeding fluid from the pressure cavity And a means for forming a hydrostatic pressure pool between the outer surface of the pressure plate and the supporting surface of the supporting means facing it, the means for forming the hydrostatic pressure pool. , First means for forming a first pressure pool, said first means being such that the fluid in said first pressure pool is at a continuous, substantially outlet pressure. To the discharge passage means, and further comprising second means for forming a second pressure pool and a timing passage means intermittently connecting the second pressure pool to the pressure cavity, A rotary hydraulic device, wherein the hydrostatic fluid pressure applied to the pressure plate by the first and second pools varies as a function of rotation of the rotor. 17. The device of claim 16 wherein said timing passage means extends through said rotor and said pressure plate. 18. The first timing passage means, wherein the timing passage means extends through the rotor and opens adjacent to the pressure plate, and intermittently with the first timing passage means when the rotor rotates. 18. The device of claim 17 including second timing passage means on the pressure plate arranged to align with. 19. The device of claim 18, wherein the first timing passage means in the rotor comprises a plurality of first timing passage means each disposed between adjacent pairs of vanes. 20. The vanes / wherein the timing passage means in the rotor and the pressure plate have fluid pressure in the second pool between the suction passage means and the discharge passage means in the fluid pressure cavity.
20. The device of claim 19, configured and arranged to vary as a function of the number of rotor segments. 21. The number of vane / rotor segments in the fluid pressure cavity is N, N + 1, N, N + 1. ． ． And N is configured to be a non-zero integer, and the timing passage means includes the second pressure from the pressure cavity when the N vane / rotor segment is in the pressure cavity. Blocks the flow of fluid to the pool, N
21. The device of claim 20, wherein fluid flow is released from the pressure cavity to the second pressure pool when there are +1 vane / rotor segments in the pressure cavity. 22. The second pressure pool is radially surrounded by the first pressure pool.
8 devices. 23. The device of claim 22, wherein the first pressure pool extends entirely around the axis of rotation of the rotor. 24. The first pressure pool has a non-uniform radial dimension about the axis and a minimum radial dimension in the pressure cavity from a radially inner side of the suction passage means, Has a maximum radial dimension adjacent the discharge passage means from the pressure cavity,
24. The device of claim 23, wherein the second pressure pool is disposed in a portion of the first pool having the largest dimension. 25. The timing passage means in the rotor and pressure plate are configured and arranged to communicate with two adjacent vane / rotor segment skeins in the pressure cavity at the same time as the second pressure pool. 19. The device of claim 18, 26. The second means for forming the second pressure pool comprises passage means interconnecting the timing passage means in the pressure plate, the vane / rotor segment at a higher pressure. Fluid in one of the vanes / rotor segments at a lower pressure through the timing passage means and the passage means in the second pressure pool to the other of the vane / rotor segments to predict fluid in the other segment. 26. The device of claim 25, which compresses. 27. The device of claim 26, wherein the passage means in the second pressure pool comprises an orifice. 28. A rotary hydraulic device, said housing means comprising: a housing means provided for rotation within the housing and having a bearing surface; an outer surface facing said bearing surface; and an inner surface. An upper pressure plate, a rotor provided for rotation adjacent to the inner surface of the pressure plate, a plurality of slots and a plurality of vanes within the slots, and within the housing radially surrounding the rotor. A cam ring having a radially inwardly facing surface defining a vane track and at least one fluid pressure cavity between the surface and the rotor; and for delivering fluid to the pressure cavity. Suction of fluid including suction passage means, and discharge passage for feeding fluid from the pressure cavity A fluid outlet including means, sealing means between the support surface and the outer surface for forming a fluid pool, and in the rotor and the pressure plate, the pressure cavity as a function of rotation of the rotor A rotary hydraulic device comprising: timing passage means for intermittently connecting the fluid to the fluid pool. 29. The device of claim 28, wherein the timing passage means in the rotor includes a plurality of passage means opening between adjacent vanes at a periphery of the rotor. 30. The timing passage means in the rotor and pressure plate of the vane / rotor segment wherein the fluid pressure in the pool is in the fluid pressure cavity between the suction passage means and the discharge passage means. 30. The device of claim 29, configured and arranged to vary as a function of number. 31. The rotor and cam ring are configured such that the number of vane / rotor segments in the fluid pressure cavity is N, N + 1, N, N + 1. ． ． And N is configured to be a non-zero integer, and the timing passage means includes the second pressure from the pressure cavity when the N vane / rotor segment is in the pressure cavity. Blocks the flow of fluid to the pool, N
31. The device of claim 30, which opens fluid flow from the pressure cavity to the second pressure pool when there are +1 vane / rotor segments in the pressure cavity. 32. The timing passage means in the rotor and pressure plate are configured and arranged to communicate with two adjacent vane / rotor segment skeins in the pressure cavity simultaneously with the pressure pool. Device. 33. The means for forming the pressure pool comprises passage means interconnecting the timing passage means in the pressure plate, wherein the fluid in one of the vane / rotor segments at a higher pressure is 33. The device of claim 32, which flows through the timing passage means and the passage means in the pressure pool to the other of the vane / rotor segments at a lower pressure to precompress fluid in the other segment. 34. The device of claim 33, wherein the passage means in the pressure pool comprises an orifice. 35. A rotary hydraulic device, comprising: a housing provided in a non-rotating manner within the housing and including support means having a surface; and a rotor provided to rotate adjacent to the surface.
A plurality of slots and a plurality of vanes in the slots; a radially inwardly facing surface that is provided in the housing to radially surround the rotor and forms a vane track; and between the surface and the rotor. A cam ring having at least one fluid pressure cavity; a fluid suction including suction passage means for delivering fluid to the pressure cavity; and a fluid including discharge passage means for delivering fluid from the pressure cavity An outlet and timing passage means in the rotor and the support means for intermittently connecting adjacent vane / rotor segments in the pressure cavity, to one of the vane / rotor segments at higher pressure Some fluid is at a lower pressure through the timing passage means. Flows to the other on / rotor segments, the fluid in said other segment to precompression, rotary hydraulic device. 36. The support means includes a plate on the support means having an outer surface facing the surface, and sealing means between the surface and the outer surface to form a fluid pool, 36. The device of claim 35, wherein the timing passage means in the rotor and the support means intermittently connect the pressure cavity to the fluid pool as a function of rotation of the rotor. 37. The device of claim 36, wherein the timing passage means in the rotor includes a plurality of passage means opening between adjacent vanes at a periphery of the rotor. 38. The device of claim 35, wherein the timing passage means in the support means comprises an orifice. 39. The device of claim 14, wherein multi-stage orifices are disposed in the timing passage and the second pressure pool to reduce pressure stepwise and reduce outgassing and consequent cavitation. 40. The device of claim 26, wherein a multi-stage orifice is disposed in the timing passage and the second pressure pool to reduce pressure stepwise and reduce outgassing and consequent cavitation. 41. The device of claim 35, wherein the timing passage means is provided with a multi-stage orifice to reduce pressure stepwise and reduce outgassing and consequent cavitation. 42. A rotary hydraulic device for positioning a vane pump cartridge axially and radially to provide a non-rotating feature, and for housing a housing containing fluid inlet and outlet ports and to drive a rotary group of pumps. A vane pump consisting of two shafts, a bearing-supported shaft, a shaft seal for containing a fluid discharge in the housing, and two pairs of a support plate and a flexible side plate, each pair being located on one side of the cam ring. A cartridge, a rotor having a radial slot and a vane located in the cam ring and surrounded by two pairs of a support plate and a flexible side plate; a support plate and a flexible side plate The two pairs of suction port passages and exhalation port passages, each supporting play Includes a hydrostatic pressure pool between the support plate and an adjacent flexible side plate, the size and shape of the hydrostatic pressure pool depending on the pressure distribution between the valve surface of the flexible side plate and the rotating group. The hydrostatic pressure of the hydrostatic pressure pool is at least equal to or slightly greater than the segregated hydrostatic pressure of the pressure distribution on the valve surface of the flexible side plate, and The height of the inner support surface is slightly lower than the support area around the support plate to allow the flexible side plates to disengage from the rotating group and to contour the radial surface of the hydrostatic pressure pool. Rotary hydraulic device having defined elastic and reinforcing materials to define and seal a hydrostatic pressure pool region. 43. A rotary hydraulic device for positioning a vane pump cartridge axially and radially to provide a non-rotating feature, and for housing a housing including fluid inlet and outlet ports and for driving a rotary group of pumps. A vane pump consisting of two shafts, a bearing-supported shaft, a shaft seal for containing a fluid discharge in the housing, and two pairs of a support plate and a flexible side plate, each pair being located on one side of the cam ring. A cartridge, a rotor having a radial slot and a vane located in the cam ring and surrounded by two pairs of a support plate and a flexible side plate; a support plate and a flexible side plate The two pairs of suction port passages and exhalation port passages, each supporting play Includes a hydrostatic pressure pool between the support plate and an adjacent flexible side plate, the size and shape of the hydrostatic pressure pool depending on the pressure distribution between the valve surface of the flexible side plate and the rotating group. The hydrostatic pressure of the hydrostatic pressure pool is at least equal to or slightly greater than the segregated hydrostatic pressure of the pressure distribution on the valve surface of the flexible side plate, and The height of the inner support surface is slightly lower than the support area around the support plate to allow the flexible side plates to disengage from the rotating group and to contour the radial surface of the hydrostatic pressure pool. Have a resilient and stiffening material to define and seal the hydrostatic pressure pool area and are raised and isolated within the hydrostatic pressure pool in the vicinity of each discharge port. Islands are positioned and the pressure sensing passages on each flexible side plate are positioned with respect to the associated isolated islands to reduce the area of interest if the two vane / rotor segments are at discharge pressure. Outflow to the outlet and pressurize the area to the outlet pressure if the three vane / rotor segments are at the outlet pressure, and make the ports in the rotor intermittent with the timing ports on the valve surface of the flexible side plate. Alignment to control and balance the opposite axial hydrostatic pressure to the flexible side plate,
Rotating hydraulic device.